In a fuel cell vehicle using high-pressure hydrogen, a safety valve is employed to release hydrogen to reduce pressure of hydrogen when temperature rises in a hydrogen tank where the high-pressure hydrogen is stored (See JP 2002-206696A). The safety valve is provided in the vicinity of the hydrogen tank and sealed by metal having low melting point. Thus, the safety valve does not operate in normal conditions. However, when the metal is melted as the temperature rises in the hydrogen tank, high-pressure gas pushes a plug of the safety valve so as to open the safety valve. As a result, the hydrogen is released to prevent internal pressure inside the hydrogen tank from increasing.
In addition, a hydrogen burst generates large energy due to high pressure of the hydrogen when the hydrogen is released into the air. Therefore, in a well-known technology, a shielding member is provided in a release outlet to disperse the hydrogen so as to reduce outside influence (See JP 2004-204956A).
However, a vehicle is considered to be used under various conditions. For instance, a release outlet of a safety valve may be blocked caused by frozen snow, water, or the like when a fuel cell vehicle is used under low temperature conditions such as snowfalls. Nevertheless, no technology taking these conditions into consideration is disclosed in the conventional technologies described above. Therefore, even though a safety valve is employed, it is predicted that the safety valve does not function depending on position where a release outlet is placed.
In view of the conventional problem described above, it is an object of the present invention to provide installation structure of a release pipe in a fuel cell vehicle and a fuel gas vehicle in order that a safety valve can surely function without a release outlet of the safety valve being blocked even under low temperature conditions.